Process for the treatment of comminuted carbonaceous material and the like in electric furnaces and the like



Oct. 15, 1929. J. J. NAUGLE 1,731,474

PROCESS FOR THE TREATMENT OF COMMINUTED CARBONACEOUS MATERIAL AND THE LIKE, IN ELECTRIC FURNACES AND THE LIKE Filed April 21, 1923 2 Sheets-Sheet 1 INVENTOR JOHN J. A/AUGLE A TTOR/VEY 15, 1929- J. J. NAUGLE 7 PROCESS FOR THE TREATMENT OF COMMINUTED CARBONACEOUS MATERIAL AND THE LIKE, IN ELECTRIC FURNACES AND THE LIKE Filed April 21, 1923 Z-Sheets-Sheet 2 [33 34 P .az 54 INVENTOR JbH/v I NA'UGLE,

A TTORNEY Patented Oct. 15, 1929 UNITED STATES rivraa'r OFFICE JOHN J. NAUGLE, OF BROOKLYN, NEW YORK PROCESS FOR THE TREATMENT OF COMMINUTED CABBON ACEOUS MATERIAL AND T KE LIKE IN ELECTRIC FURNACES AND THE LIKE Application filed A ril 21,

D als designated of a pure grade of carbon characterized by a very low ash or mineral content, high electrical conductivity, and a remarkably high degree of activation corresponding to a high degree oi decolorizing power. It is an object of the present invention to devise methods of the character specified above which shall be exceedingly simple in operation, requiring comparatively simple apparatus and a minimum of time, labor and material for this purpose, which shall produce the desired product in the desired condition of high purity, high conductivity and a high degree of activation anddecolorizing power, which shall effect such a distribution of heat through the mass of material being treated, during the various stages of its treat- 1 ment, as shall-be best calculated to bring about the desired result in the most expeditious and reliable manner; and which shall render possible a very high yield of the desired end product by a continuous, rather than by a batch, process. I

In the accompanying specification I shall describe an illustrative embodiment of the method of the present invention. In the accompanying specification I shall also describe', and in the annexed drawing show, one form of apparatus in which the method of i the present invention may be conveniently 40 practiced. It is, however, to be clearly understood that my invention is not limited to the specific embodiment of the process described herein, nor to the use of the particular form of apparatus shown and described herein, said apparatus forming the subject matter of a separate application for Letters Patent filed by me of even date herewith.

In order that my invention may be more clearly understood, .reference may be made to a co-pending application of mine filed of Carbon dioxide 1923. Serial No. 883,843.

even date herewith, Serial No. 633,640 and entitled Method of treating carbonaceous material in an electric furnace or the like.

In practicing the aforesaid illustrative embodiment of the method of the present invention, I first take any suitable raw material, preferably a carbonaceous material, in comminuted or finely divided form. While various types of comminuted carbonaceous material may be treated with success in accordance with the principles of the present invention, either in the production of a highly activated carbon from the raw material, or in the revivification of spent decolorizing carbon, I shall describe the present invention as applied more particularly to the purification of a highly activated carbon from carbonized lignin residues in comminuted form, such residues being obtained by carbonizing the cooking liquors derived from the treatment of wood by the alkali (soda) process in the production of wood pulp.

Taking, for example, the raw material speclfied above, which material comprises comminuted carbonized lignin residues, such material may have an average analysis as follows:

Analysis of comminuted carbonized Zz'gm'n residues Carbon i? Ash '10 Analysis of ash Silicious matter 0. 13 Silica 0.75 Ferric oxide i 0. 34 Alumina- 0. 47 Lime, CaO 0. 23 Magnesia, MgO 0. 11 Chlorine as chlorides O. 47 Sulphuric anhyd'ride ,2. 65 1. 0O Alkalies (by difl.) 3. 85

This material contains certain volatile matter and also certain fusible mineral substances which have a high electrical resistance and which serve substantially to reduce the conductivityof the rawmaterial.

I now heat the mass of raw material specified above so as to expel the volatile substances and to fuse the contained mineral substances, characterized by a high resistivity, for the subsequent removal of such fused mineral substances. This I preferably do by subjecting the raw material to the successive action of degrees of heat of varying intensities. While the process ma be carried out by Suecessivel subjecting t e raw material to degrees 0 heat which are relatively increasing, I have found that to subject the material to succesively decreasing stages of heat is eminently as satisfactory but I do not wlsh to be confined to this articular method. In accordance with th1s statement I will describe the process in which the degrees ofheat to which the material is successively subjected diminish during each successive stage of treatment. For example, if the material is subjected to three successivdstages of heat treatment, it may be heated to a temperature from 800 to 1500 C. in the first stage, from 600 to 1200 C. in the second stage, and from 400 to 600 C. in the third and last stage, where a highly activated decolorizing carbon is manufactured from the raw material specified; or up to 600 C. in the first stage, up to 500 C. in the second stage, and up to 400 C. in the third and last stage, where spent decolorizing carbons are treated for revivification In order to eifect the desired heat treatment of the raw material in the successive stages, corresponding to successively diminishing degrees of heat, I prefer to subject such material to the successive action of electric currents of varying, such as diminishing, densimixture and stirrin ties. Such electric currents should preferably be passed directly through the raw materlal during its treatment. For example, in the first stage of treatment for the manufacture of a highly activated decolorizing carbon, a comparatively high current density should be employed, while in the second stage of the treatment a moderate current density should be employed; and in the third and last stage of thetreatment a comparatively low current density should be used.

In carrying out the process, the material is continuously fed into the successive heating chambers so as to be subjected to the electric currents of varying, such as diminishing, den-- sities for generating degrees of heat of correspondingly var in such as diminishing, in-

tensities. Pre era ly, the current is passed into the material between relatively movable electrodes which serve to effect an intimate action of the material being treated. Fee ing means may be provided within the heating chambers to continuously advance the material during the successive stages of treatment and to feed the material from one heating chamber to the next, thus subjecting the material being treated to successive sets of electrodes for passing electric currents through the material in contact with the particular set of electrodes. v

The heat treatments described eflect a substantial elimination of volatile substances present in the raw material being treated and serve also to fuse the fusible mineral substances present in the mass bein treated, which mineral substances, when used, are found to adhere to the electrodes or to other parts of the apparatus, and are thus removed from the material being treated in accordaalce with the principles of the present invention. The removal of such mineral substances, characterized by a high electrical resistivity, serves to substantially increase the conductivity and purity of the treated product, and thus to yield a product having a correspondingly high degree of activation and decolorizmg power.

The present method may be combined with considerable success with the means andmethod described and claimed in my copending application, filed May 22, 1922, Serial No. 562,828, and entitled Prefiltering means and method, especially so far as the preliminar treatment of the raw materials is concerne particularly to effect, as by decantation from a watery suspension of such material, a more or less partial preliminary separation by gravity of the portions of the material richer in carbon from the portions of thematerial poorer in carbon and containing an excess of heavy mineral substances. I may also use the feature of effecting a purification of the final product by forced filtration, under pressure, through a layer of the final product, of an aqueous acidified fluid and of wash waters. I may also add to the charge of material being treated in accordance with the principles of the method of the present invention certain reagents, such as sodium fluoride, which will have the property of eliminating one or more of the mineral substances present in the charge, particularly silica, in the form of volatile by-products, such as silicon fluoride.

In the practice of the foregoing method, I may also provide means for eliminating the gaseous products of the reaction continuously, or from time to time, and I mav also provide means for testing the product during each of the stages of its treatment in accordance with the method of the present'invention. I may also provide means for introducing an atmosphere of any desired gas into the apparatus in which the process is being carried out. If desired, this gas may be either a neutral gas, such as nitrogen, calculated to diminish combustion of the material treated, if such material is combustible, or may be some gas intended to react with some of the impurities present in the material being treated soas to yield a final product of the maximum purit electrical conductivity and activation and ecolorizing power.

The resulting product possesses many advantages for the intended purpose, since it can be very cheaply made in accordance with the method of the present invention, and possesses the desired quality of high conductivity, corresponding to a remarkably high degree of activation and decolorizing power. An average analysis-of such'material is as follows:

Analysis of the final product Per cent Carbon 97.60 Ash 2. 40

Analysis ofash Calcium 0.16 Sodium, Na O O. 35 Magnesium, MgO O. 16 Chlorides, (C1 0. O.

Sulphates (S0,) Silica, SiO 0.50 Iron and alumina (FY5 0 Al O 0.39

This roduct is also characterized by a very big degree of purity, corresponding to a hlgh electrical conductivity and a high dcree of activation and decolorizing power.

he conductivity of the final product is often increased as much as five times that of the raw material treated, and its mineral content is often reduced to as low as one-fourth or less that of the raw material treated in accordance with the method of the present invention. The method itself is exceedingly simple to practice, requiring-comparatively simple apparatus and a minimum of time, labor, power and material for this purpose. The method is also admirably calculated to produce the desired end product in the desired condition of purity, high conductivity and high degree of activation and decolorizing power. This method is also very economical in view of the very high yield which may be obtained by its practice as compared with the methods hitherto employed for revivifying spent decolorizing carbon or for producing highly activated carbons for decolorizing purposes from the raw materials.

Referring to the drawing, wherein I have illustrated one form of apparatus in which the method outlined above may be conveniently practiced:

Fig. 1 is a side View, partly broken away, showing the aforesaid furnace in which the aforesaid illustrative embodiment of the method of the present invention may be practiced with considerable success;

2 is a longitudinal sectional view of the same, partly in elevation;

Fig. 3 is a cross sectional view, elevation, taken along line 33 of the drawing;

artly in ig. 2 of collars or extensions 36 and 38, respectively,

Fig. 4 is a side view of one form of central or inner electrode which may be used with 10 comprises a plurality of, here shown as three, sections 11, 12 and 13,'these sections being made of metallic materiahsuch as cast iron or steel, and serving as the external electrodes of the device, as subsequently described in greater detail.

At 14 I have shown an inlet provided with a suitable type of feeding means, such as the feed hopper generally indicated by reference character 15 and including the feeding member 16 rotatably operated from any suitable source of power, not here deemed necessary to be shown. At the outlet end of the machine, I have provided a discharge hopper 17 communicating with a discharge chute 18 leading to any suitable bin or other stora e device in which the finished material may be stored.

Each of the sections 11, 12 and 13 is provided with the flanged ends 19, 19; 20, 20; and 21, 21, respectively, while the inner ends of the inlet 14 and the outlet 17 are provided with the flanged ends 22 and 23, respectively. Insulating gaskets 24 are inserted between the meeting faces of the flanged ends just referred to, so that the successive sections 11, 12 and 13 of the casing 10 will be insulated from each other and from the inlet 14 and the outlet 17. i

Suitably mounted for rotation within the casing 10 is an inner electrode or shaft generally indicated by reference' character 30. The shaft 30 is also divided into a series of, here shown as three, sections 31, 32 and 33, corresponding in number to the sections 11, 12 and 13 of the casing 10. Each of, the sections 31, 32 and 33 is provided with a series of conducting vanes or electrodes 34 which are preferably integral with the respective I sections of the shaft 30.

One end 35 of the shaft 30 passes through the collar 36 forming an extension of the inlet 14 and preferably inte ral therewith. The other end 37 of the s aft 30 passes through a similar collar 38 forming an extension of the outlet 17 and being preferably integral herewith. Preferably, the ends 35 and 37 of the shaft 30 are insulated from the so that the shaft 30, and the sections 31, 32 and 33 of which the same is composed, in-

cluding also the conducting vanes or elecwith the flanged portions 42 and 43 at its ends,

Gaskets 44 are inserted between the opposed flanged end portions of the sections 31, 32' and 33 of the shaft 30, so that the various sectlons of the shaft will be insulated from each other. The section .31 is preferably hollow so as to permit the passage therethrough of an auxiliary cable or conductor 45 which is insulated from the section 31 and also from the section 33, but which is in electrical connection at 1ts inner end, as indicated at 46, with the mtermediate section 32, and at its outer end, as ind cated at 47, with a flanged sleeve or thimble 48 carried by the shaft 45, but lnsulated therefrom, all for a purpose subsequently to be described in greater detail.

Within the casing 10 are means generally indicated by reference character 50 for efficiently mixing and stirring the material treated in the furnace, and for continuously advancing the same from one heating1 zone to the next during the treatment. W ile various devices may be employed for this purpose, I prefer to employ the means shown 1n the drawing, preferably Fig. 2 of the same, and comprising a plurality of spiral elements 51 carried by the successive sections 31, 32 and 33 of the shaft 30, as by means of the supporting arms of brackets 52. As shown in Fig. 3 of the drawing, the arms or brackets 52 are supported at their inner ends 53 by the respective sections 31 32 and 33 of the shaft 30, and carry at their outer ends, indicated by reference character 54, the spiral elements 51 of the feeding means 50. It will also be noted that in the form illustrated, three spiral elements 51 are required for one complete turn of the spiral feeding means 50. Preferably, the spiral feeding means 50 and the arms or brackets 52 supporting the same, are of insulating material, or covered with insulating' material, so as not to serve as current carriers.

At I have shown an exhaust pipe, communicating by means of the connection pipes 61,62 and 63, with the successive sections 11, 12 and'13 of the casing 10. The exhaust pipe (30v leads to a condenser anda water seal, so as to serve as an exhaust for the gaseous products of combustion or reaction, or for any other gas which may be present or which may be admitted to the charge within the furnace.

At I have indicated a tube communicating, by means of the connections 71, 72 and 73, with the successive sections 11, 12 and 13 of the casin 10. The gas inlet tube 70 may be connecte with a source of supply, of gas,

referably under pressure, intended to be irected to the charge within the furnace. This gas may be either a neutral gas, to provide an inactive atmos here within the furnace to lessen combustion, such as nitrogen gas, for exam le, or may be some other as intended to tahe part in the reaction wit in the furnace, as to serve to eliminate in gaseous form certain undesirable impurities present in the charge of material within the furnace.

At 81, 82 and 83 I have indicated sample test holes provided with the covers 84, 85 and 86, respectivel permitting the charge within each of the urnace sections 11, 12 and 13 to be sampled and examined from time to time, so as to determine the condition of the charge within the furnace at its different stages of treatment.

In order to provide proper electrical connections for the electrodes comprising the case sections 11, 12 and 13, and the sections 31, 32 and 33 of the shaft 30 carrying the conducting vanes or electrodes 34, I may employ the means shown more clearly in Figs. 4 and 7 of the drawing, and comprising the brushes 91, 92 and 93 contacting with the annular ends 39,43 and 48 of the shaft sections 31 and 33, and the conducting thimble 47, respectively. The brushes 91, 92 and 93 are connected, by means. of the wires 94, 95 and 96, with one of the poles, such as the positivelpole, of a direct current generator of suitable capacit this generator being preferably provide with a shunt wound field. The casing sections 11, 12 and 13 are connected, at the points 11 12 and 13', with the wires 97, 98 and 99, leading to the remaining pole, that is, the negative pole, of the shunt wound generator referred to, which enerator is not here deemed necessary to he s own.

This system of electrical distribution is more particularly described and claimed in an application which will be filed.

In order to efl'ecta relative movement, such as a relative rotation, of the cooperating sets of electrodes each comprising a casing section and a shaft section carrying the conducting vanes or electrodes 34, I employ any suitable means for effecting the desired relative movement, such as the spiral gear 100 cooperating with the worm 101 driven from any suitable source of power, not here deemed necessary to be shown. By the operative engagement of the worm 101 with the spiral gear 100, the shaft 30, comprising the sections 31, 32 and 33, carrying the conducting vanes or electrodes 34, is rotated at any suitable rate of speed relatively to the casing 10 comprising the casing section 11, 12 and 13. The feeding means 50. in the form of' the plurality of spiral feeding elements described above, being carried by the shaft 30, will likewise be rotated with the same, and will thus serve. to feed or advance the material during the treat-ment and also to assist in thoroughly stirring and mixin the same.

The manner 0 assemblin the above machine will be substantially cIear from the foregoing description. The manner of operating the machine, will also be substantially clear from the foregoing description and may be briefly summarized as follows: In commeneina the operation of the furnace, the material to be treated, such as the comminuted carbonized lignin residues referred to, is fed into the-feed hopper 15 and is thereupon continuously fed into the inlet 14 of the machine by means of the rotatin feeding element 16. From the inlet 14 tile material to be treated is fed into the first of the heating zones'or reaction chambers, in this case the heating zone or reaction chamber within the casing section 11. From the section 11 the material is fed into the successive heating zones or chambers within the successive casing sections 12 and 13, by means of the feeding means 50.

By the operation of the gears 100 and .101, the shaft 30, comprising the shaft section 31, 32 and 33 carrying the conducting vanes or electrodes 34, is caused to rotate with respect to the sections 11, 12 and 13 of the casing. At the same time, the feeding means 50, also carried by the shaft 30 and the sections thereof, is caused to rotate, thus causing the rotation and operation of the spiral feeding elements 51, 1 which, together with their supporting arms 52, are insulated from the shaft 30 and the sections 31, 32 and 33 of the same, and also from the conducting vanes or electrodes 34, as well as from the casing 10 and the casing sections 11, 12 and 13 of the casing 10. This relative rotation causes the material being treated, here designated by reference character M, to be continuously fed from one heating zone or reaction chamber into the next, and to be-thus subjected to electric currents of varying densities and correspondingly varying degrees of heat. In the present instance, for the particular purpose in view,

the current densities, and thus the degrees of heat, diminsh from one heating zone or reaction chamber to the next. in the direction of the feed of the material being treated.

The time of treatment may vary, but is usually from about 15 to minutes. The

treatment should be continued long enough to expel substantially all of the volatilematters contained in the raw material, and to fuse the fusible mineral substances present therein to the condition of small aggregates or clinkers. These will be found to adhere to the sections 31, 32 and 33 of the shaft 30, and to the conducting vanes or electrodes 34 carried thereby, as well as to the spiral feeding elements'51, and occasionally'to the inner walls of the sections 11, 12 and 13 of the casing 10.

The products of combustion are drawn ofi through the gas outlet 60 by means of the connecting tubes 61, 62 and 6.3- communicating with the respective casing sections 11, 12 and 13. The products of combustion or'other gases or reaction are led to a condenser and a water-seal. By means of the pipe having the connecting tubes 71, 72 and 73 communicating with the respective sections 11, 12 and 13 of the casing 10, I may admit a suitable gas to the various reaction chambers, such as nitrogen gas, if it is desired to minimize combustion and to carry on the reaction in a neutral or inactive atmosphere, or some other gas or gases which it may be desired to add and which will take part in the reaction, such be fed through the machine and be mixed and stirred; and also the current densities and heat intensities which should best be employed with the particular material being treated in the machine. The finished product passes out of the machine through the outlet 17 into the discharge hopper 18, leading to a bin or other suitable storage receptacle.

It may here be stated that the carbonized lignin residues referred to herein are the residues remaining after leaching the residues obtained by carbonizing the spent or used cooking liquors derived in the treatment of wood by the alkali (soda) process in the production of wood pulp; and that the terms activation and decolorizing, or' their equivalents, as used in the specification and claims, include also deodorization, purification and filtration.

It may also be stated'that' the heat treatment to which the raw material, such as the carbonized lignin residues referred to, is sub jected, serves also to volatilize a part, at least,

. of the more readily volatile mineral constituents of the material being treated to produce the product of the present invention. The product is thus of an unusually high degree of purity and of comparatively low specific grav- 1ty, weighing as low as about six, and up to about nine, pounds per cubic foot, whereas the raw material weighs from about eighteen down to about ten, pounds per cubic foot. The product is also remarkably porous, of very uniform quality, and of very high efiiciency.

Since I prefer, also, that the carbon of the present invention shall, in the course of its preparation, or otherwise, be deprived of .a substantial part of the fines or finer particles, the presence of which would tend to make the product unstable, to render it more combustible and to diminish its efliciency', which fines usually comprise from about twenty, to about thirty, per cent of the weight of the material treated for the production of the product which may be made with a high yield, which is remarkably stable, which is .less combustible than other products of a similar nature, which shows a very low percentage of loss during its manufacture and during its use for filtration and subsequent revivification, and which tends to yield a product of constantly increasing efliciency during successive revivifications.

This reduction in the percentage of fines, or finer particles, may be effected by admitting air in regulated quantities through the inlet pipe 70 and the branches 71, 72 and 73 of the same leading to the casing sections 11, 12and 13, respectively. The amount of a1r,

for other oxidizing or oxygen-containing gases, admitted to the heating or reaction chambers within the casing sections 11, 12 and 13 may be regulated by the respective valves 71', 72' and 73'. This amount of air, or its equivalent, may vary for the different chambers, since a greater degree of combustion will generally be desired in the first reaction chamber 11 than in the subsequent reaction chambers 12 and 13. It may here 'be stated that the heat of combustion resulting from the burning of the fines referred to, assists in the treatment of the carbon and reduces the amount of electric current which would otherwise required to generate the desired degree of heat in each of the reaction chambers. The addition of air, or its equivalent, in regulated quantities, as above set forth, is found to have avery beneficial action upon the product, accelerating the reaction and acting, in

some way, to produce a product of greater purity, apparently by the elimination of some of the more volatile 'mineral constituents of the raw material being treated for the production of the final product.

Instead of air, or, sometimes, together with air, or in place thereof, as by subjecting the material being treated to alternate treatments with air and steam, steam in regulated quantities may likewise be admitted to the respective with a part or .all of the mineral impurities present in the charge within the furnace, particularly silicious mineral impurities, such as silicaand silicates, to produce volatile compounds Which would thus" be eliminated'from the final product. Where the mineral impurity desired to be eliminated is silica, and

the addition agent sodium fluoride, silicon fluoride is eliminated, with the roduction of a soluble byproduct which may e eliminated by washing the product. It may also be pointed out that the casing sections 11, 12 and 13 may be of difierent lengths, thus permitting the raw material to be subjected to treatment for diiferent lengthsof time in the respective reaction chambers, depending upon the particular treatment desired to be given such material in the particular chambers and under the particular atmospheric'conditions,

as to air, steam and products of combustion or other reaction, or otherwise, prevailing in the particular reaction chambers. I

For the purpose of comparing the specific resistivity, or conductivity, as desired, of the raw material and of the final product, it may be stated that the total resistance of a mass of the raw material (in this case the carbonized lignin residues referred to) within a tube one inch long and one and seven-sixteenth inches in diameter, under a total pressure of one kilogram, was found to be about 167 ohms, corresponding to a resistance of about 6.28ohms per cubic centimeter. The total resistance of a mass of the final product within a tube of the same dimensions and under a similar total pressure, was found to be about 33.5 ohms, corresponding to a resistance of about 1.26 ohms per cubic centimeter.

Another very valuable characteristic of the product of the present invention is that it is almost absolutely neutral, being neutral to phenolphthalein. This is probably the re sult of the'manner in which the carbon is preferably produced, which consists in initially subjecting the raw material to a comparatively high temperature, which apparently converts the sulphates present in the raw material being treated, principally calcium and sodium sulphates, into sulphides, by the reducing action of the carbon, the sulphides, at a comparatively low temperature, being converted into the normal carbonates of calcium and sodium,respectively, to yield a neutral carbon. If the temperature is again raised so as to be comparatively high, the carbonates are apparently calcined and converted into the highly alkaline oxides. This is to be avoided since the neutralization of such an alkaline carbon by the addition of acid will tend to yield an acid carbon, which is highly undesirable, since acid carbons tend to invert sugar, where the carbons are used for the purification or filtration of sugar solutions, while alkaline carbons tend to form slimes which retard the rate of filtration or purifi- .cation; while the carbon of the present invention, being, as it is, absolutely neutral, no slimes tend to be formed andthus a high rate of filtration or purification is possible, while the absence of acid in the carbon avoids the inversion of sugar if sugar solutions are purified or filtered through the product of thepresent invention.

What I claim as my invention is: v

1. The process of treating comminuted carbonaceous material, which comprises subjecting suchmaterial to the successive action of electric currents of relatively varying densities.

2. The process of treating comminuted carbonaceous material, which comprises sub jecting such material to the successive action of electric currents of diminishing densities.

3. The process of treating. comminuted material, which comprises passing through such material a succession of electric currents of relatively different densities.

4. The process of treating comminuted material, which comprises passing through such material a succession of electric currents.

of decreasing densities.

5. The process of treating comminuted material, which comprises stirring 'such ma- I terial while passing through such material a succession of electric currents of decreasing densities.

' 6. The process of treating comminuted carbonaceous material, which comprises continuously advancing such material while subjeeting-such material to the successive action of electric currents of diminishing densities.

7. The process of treating comminuted material, which comprises continuously stirring and advancing such material while passing through such material a succession of electric currents of relatively different densities.

8. The process of treating comminuted carbonaceous material, which comprises advancing and stirring such material while subecting such material to the successive action of electric currents of relatively varying densities.

'9. The process of treating comminuted.

carbonaceous material containing fusible mineral substance, which comprises continuously advancing such material while sub ecting such material to the successive action of electric currents of diminishing densities and removing fused mineral substance from such material.

10. The process of treating comminuted material containing fusible mineral substance, which comprises stirring such material while passing through such material a successionof electric currents of decreasing densities and continuously removing fused mineral substance from such material.

'11. The process of treating comminuted material containing fusible mineral substance, which comprises passing 1 through such material a succession of electric currents of relatively different densities and removing fused mineral substance from such material during each of the successive-stages of subjection of such material to the action of the electric currents of different densities.

12. The process of treating comminuted' carbonaceous material containing fusible mineralsubstance, which comprises advancing and stirring such material while subjecting such material to the successive action of electric currents of relatively varying densities and continuously removing fused mineral substance from such material during each of the successive stages of subjection of such material to the action of electric currents of varying densities.

13. The process of treating comminuted carbonaceous material containing fusible.

mineral substance, which comprises subjecting such material to the successive action of electric currents of relatively varying densities and removing mineral substance from such material.

14. The process of treating comminuted carbonaceous .material containing fusible mineral substance, which comprises subjecting such material to the successive action of electric currents of diminishing densities and removing mineral substance from such material during each of the successive, stages of" subjectionof such material to the action of the electriccurrents of diminishing densities. 15. The process of treating comminuted material containing fusible mineral substance, which comprises continuously stirring and advancing such material while passing through such material a-succession of electric currents of relatively different densities and continuously removing mineral sub-- stance from such material during each of the successive stages of subjection of such material to the action of electric currents of difjecting such material to the successive action of relatively varying degrees of heat and simultaneously removing fused mineral substance fromsuch material.

18. The process of treating comminuted carbonaceous or like material containing fusible mineral substances, which comprises subjecting such material to the successive action of diminishing degrees of heat and continuously removing fused mineral substance from such material during each of the successive stages of subject-ion of such material to the action of the diminishing degrees of heat.

19. The process of treating comminuted carbonaceous or like material containing fusible mineral substances, which comprises stirring such material while subjecting such material to the successive action of varying degrees of heat and removing fused mineral" cessive action of diminishing degrees "of heat and continuously removing fused mineral substance from such material.

passing such material from one heating zone to another heating zone of lesser heat intensity, and removing fused mineral substance from such material.

22. The process of treating comminuted carbonaceous and like material containing fusible mineral substances, which comprises continuously passing such material through a succession of heating zones of varying heat intensity, and continuously removin fused mineral substance from such materia 23. The process of treating comminuted carbonaceous and like material containing fusible mineral substances, which comprises passing such material from one heating zone to another heating zone of lesser heat intensity while stirring such material and removing fused mineral substance from such material in each of said heating zones.

24. The process of treating comminuted carbonaceous and like material containing fusible mineral substances, which comprises continuously passing such material through.

a succession of heating zones of varying heat intensity while continuously stirring such material and continuously removing fused mineral substance from such material in each of said heating zones.

25. The process of treating comminuted carbonaceous material containing substances of comparatively low electrical conductivity, which comprises continuously advancing such material while subjecting such material to the successive action of electric currents of diminishing densities and removing substances of comparatively low electrical conductivity from such material.

26. The process of treating comminuted material containing substances of compara tively high electrical resistance, which comprises passing through such material a succession of electric currents of relatively different densities and removing substances of comparatively high electrical resistance from such material during each of the successive stages of subjection of such material to the action of the electric currents of-relatively different densities;

27. The process of treating comminuted carbonaceous material containing substances of comparatively high electrical resistance, which comprises subjectin such material to the successive action of e ectric currents of relatively varying densities and removing substances of comparatively high electrical resistance from such material.

28. The process of treating comminuted material containing substances of comparatively low electrica conductivity, which comprises continuously stirring and advancing such material While passing through ,such material a succession of electric currents of relatively different densities and continuously removing substances of comparatively low electrical conductivity from such material during-each of the successive stages of subjection of such material to the action of elec tric currents of relatively difierent densities.

29. The process of treating comminuted carbonaceous or like material containing substances of comparatively high electrical re sistance, which comprises subjecting such material to the successive action of varying degrees of heat and removing substances of comparatively high electrical resistance from such material.

30. The process of treating comminuted carbonaceous and like material containing substances of comparatively low conductivity, which comprises passing such material from one heating zone to another heating zone of lesser heat intensity, and removing.

substances of comparatively low conductivity from such material.

31. The process of treating comminuted carbonaceous material, which comprises subj ecting such material to the successive action of electric currents of varying densities in the presence of an oxidizinggas.

32. The process of treating comminutedoxidizing gas and removing fused mineral substance from such material.

35. The process of treating comminuted material containing fusible mineral substance, Which comprises passing through such material a succession of electric currents of relatively difierent densities in the presence of a regulated amount of air and removing fused mineral substance from such material during each of the successive stages of subjection of such material to the action of the electric currents of relatively different densities.

36. The process of treating comminuted material containing fusible mineral substance, Which comprises continuously stirring and advancing such material While passing through such match 1 a succession of electric currents of relatively different densities in the presence of a regulated amount of steam and continuously removing mineral substance from such material during each of the successive stages of subjection of such material to the action of relatively electric currents of different densities.

37. The process of treating comminuted carbonaceous or like material containing fusible mineral substances which comprises subjecting such material to successive stages of relatively varying degrees of heat in the alternate presence of air and steam and removing fused mineral substance from such material, during each of said successive stages. 1

In testimony, whereof, I have signed my name to this sepcification this 30th day of March, 1923.

JOHN J. NAUGLE, 

